REDDIT · REDDIT// 6h agoSECURITY INCIDENT

GPT-5.5 leaks reasoning traces in Codex

A Reddit user says GPT-5.5-medium in Codex surfaced what looks like internal planning text while handling a coding task. The report is anecdotal, but if reproducible it points to a safety and UX bug in how Codex separates private scratchpad output from user-visible responses.

// ANALYSIS

This reads less like a dramatic model breakthrough and more like an agent wrapper failing to keep its private notes private.

–The reported output looks like fragmented planning and formatting instructions, which suggests internal reasoning or orchestration text may have been exposed
–Because this is a single Reddit report, it should be treated as a user-observed bug, not a confirmed systemic vulnerability
–If reproducible, the issue matters more for trust than correctness: coding agents need hard boundaries between hidden planning and final answers
–OpenAI explicitly pushed GPT-5.5 into Codex for agentic coding on April 23, 2026, so any trace leakage lands in a high-stakes workflow
–The linked LocalLLaMA discussion shows this kind of prompt/format leakage has been a recurring community concern for months

// TAGS

gpt-5.5ai-codingcoding-agentagenttool-usesafetysecurity

DISCOVERED

6h ago

2026-05-03

PUBLISHED

9h ago

2026-05-03

RELEVANCE

9/ 10

AUTHOR

Homeschooled316